1. Universe Today – How Spiral Galaxies Get Their Shape
Density wave theory says that the arms themselves are separate from the stars and gas and dust that travel through the density waves. The arms are the visible part of the density waves themselves, and the stars move in and out of the waves. So the arms aren’t permanent structures made of stars, even though that’s what it looks like.
Here’s a short video showing how density waves create spiral arms in galaxies.
2. Universe Today – Wow, Meade Instruments Just Filed for Bankruptcy Protection
4. Universe Today – Doug Loverro’s job is to restore American spaceflight to the ISS and the moon
5. Brown Spaceman – Future Space Missions I’m Excited About – NASA, ESA, ISRO Missions 2020 and Beyond
Each flight of a SpaceX Falcon 9 or any other orbital rocket launch is about the same as a passenger jet like a 777 flying across the Atlantic.
The larger SpaceX Super Heavy Starship will use 1kg of methane for every 3.6 kg of oxygen. The Super Heavy Booster will use 3300 tons of fuel. 717 tons of methane. The Starship will use 1200 tons of fuel or 260 tons of methane. This would be 715 tons of CO2.
Sub-orbital flights should need only need about 25% of the fuel. This would reduce Starship emissions to about 200 tons of CO2 per flight.
7. Nextbigfuture – A Hyper-Connected World With 25 Times Faster Travel Will Triple the World Economy
Geoffrey West and the Sante Fe Institute performed a study of cities and found that if the size of a city doubles, then, on average, wages, wealth, the number of patents, and the number of educational and research institutions all increase by approximately the same degree, about 15 percent. They refer to this systematic phenomenon as “superlinear scaling”: produces, and consumes, whether it’s goods, resources, or ideas. Reusable rockets could create a global city of 9-10 billion people by 2050. This would be a “city” with ten-doublings over a ten million-person city. This would be a 150% boost in per-person income.
The future history of SpaceX will be as follows:
* SpaceX capture over 60% of the commercial launch market. This has happened.
* SpaceX launches and starts operating Starlink mega constellation. 120 production Starlink satellites are already launched and the initial service will start in mid-2020. There should be 1400 Starlink satellites in orbit by the end of 2020.
* SpaceX flies Starship to orbit in 2020. In 2022 or 2023, SpaceX rolls out its ultra-rapid delivery package service.
* SpaceX annual revenue surpasses NASA’s budget by 2025
* Around 2027, SpaceX is operating over 1000 flights per day for 1 to 6-hour international deliveries.
* Around 2030, SpaceX proves the safety of rockets after millions of flights for human one-hour anywhere passenger service. There would already be over one-hundred Spaceports and thousands of Starships.
By 2040, the world will have high-speed self-driving future cars moving through tunnels at 150-200mph mainly for travel up to 200 mile range.
There will be high-speed rail in low pressure or vacuum tubes and hyperloop for travel at 500 mph to 2000 mph mainly for travel up to 1500 mile range.
Reusable rockets would provide the travel for ranges beyond 1500 miles.